Field
Embodiments described generally relate to methods for making lignocellulose composite products. More particularly, such embodiments relate to methods for making lignocellulose composite products having an increased brightness.
Description of the Related Art
The production of lignocellulose composite products generally requires an adhesive or binder to bond the discrete particulates, fibers, veneers, or other wood substrates to one another. Typical lignocellulose composite products include particleboard, fiberboard, plywood, and other composite wood products. Conventional binders used in the production of these products include urea-formaldehyde (UF) resins, melamine-formaldehyde (MF) resins, melamine-urea-formaldehyde (MUF) resins, and phenol-formaldehyde (PF) resins and produce lignocellulose composite products generally having a wood neutral color. Alternative binder compositions that do not include formaldehyde based resins, which are frequently referred to as no-added formaldehyde (NAF) resins, include tannin/hexamine based binders. These NAF resins are generally used to produce lignocellulose composite products having desired physical properties, but the color of such composite products can be significantly darker than if produced with conventional formaldehyde containing binder. From an aesthetic perspective, darker lignocellulose composite products can be undesirable.
There is a need, therefore, for improved methods for making lignocellulose composite products having an increased brightness.